While the crayfish have never been seen in the wild in America, they are popular among hobbyists. They’re banned in Missouri and Tennessee.

The European Union also banned the species from being produced, distributed, or released in the wild.

Madagascar, where the crayfish are thriving, has become concerned about the size of the population.

“There are a lot of clear advantages to being a clone,” Zimmer writes. “Marbled crayfish produce nothing but fertile offspring, allowing their populations to explode.”

It’s unclear how long the population will be able to thrive.

People on Twitter were freaking out about the discovery.

Ok: asexually reproducing lady crayfish clones are actually going to be how the world ends. I defy any of you to say you saw this coming. “For 20 yrs these crayfish have been multiplying like Tribbles. People start out w/one & a year later they have 200.” https://t.co/5Otxmm00VP